WASHINGTON — A top housing official said yesterday the Bush administration "strongly opposes" Democrats' housing rescue package, calling it a bailout that would expose taxpayers to excessive risk.

The comments by Deputy Secretary of Housing and Urban Development Roy Bernardi, in a letter sent to lawmakers, were the most forceful rejection yet by the Bush administration of a plan to let the Federal Housing Administration take on as much as $300 billion in new mortgages for financially strapped homeowners.

They came as the House Financial Services Committee began work on the bill by its chairman, Rep. Barney Frank, D-Mass. It would substantially relax the FHA's standards to reach struggling borrowers who otherwise would be ineligible.

Homeowners would have to show they could make payments on a refinanced mortgage, and lenders would have to agree to take hefty losses on the existing loans.

"We're not talking here about murderers or muggers or arsonists. We're talking about people whose misdeeds were to try too hard to find housing for their family," Frank said.

The Bush administration questions the scope and structure of the plan, although it backs the central concept: adjusting the FHA's rules so more homeowners can refinance.

An administration program made similar changes, but it is limited to borrowers who have good credit and histories of making their payments on time. It also doesn't require lenders to accept losses on existing mortgages. Doing so, Bernardi wrote, would "significantly limit lender participation."